The present invention relates to a pump assembly for a brake system that executes so-called antilock brake control or active brake control and more specifically to a support structure of a pump assembly for supporting an output shaft of an electric motor.
A brake system heretofore known includes a brake unit disposed between a wheel cylinder and a master cylinder and has an antilock brake function for preventing wheel lock and wheel slip. Further, the brake system with such a brake unit has come to perform, in addition to the antilock brake function, various other functions such as a traction control function, stability control function for obtaining a vehicle running stability and a brake assist function for assisting a braking effort of a driver.
The brake system having the above-described functions has a pump assembly including a metal housing within which brake fluid passages, a pump, etc. are disposed and an electric motor that is attached to an end surface of the housing for driving the pump and thereby controlling increase and decrease of brake fluid.
An example of a pump assembly described above is disclosed in Japanese Utility Model Provisional Publication No. 6-61637.